The present invention generally relates to devices for heating and dispensing food products, particularly vending machines for dispensing heated food products.
Money-actuated, or so-called "vending" machines have long been used to vend various different types of food products. Originally, such machines were used to vend food products which either could remain at room temperature, or which needed to be cooled. However, it has recently become increasingly popular to vend food products which are to be served warm or hot, and which therefore need to be heated.
Examples of machines which have been developed to dispense warm and/or heated food products may be found with reference to U.S. Pat. No. 4,838,455; 4,398,651; 3,620,341; 3,534,676; and 3,245,581, among others. Collectively, these patents illustrate vending machines for storing a refrigerated food product which, responsive to operation of the vending machine, is dispensed from the refrigeration unit for delivery to a heating device, followed by delivery of the heated food product from the apparatus at an appropriate dispensing point. These devices are used to dispense heated food products of different types, and generally vary depending upon the type of food product which is to be vended. However, in practice, it has been found that vending machines of this general type are subject to certain limitations.
For example, an important consideration in the dispensing of food products from vending machines is one of convenience. It is generally recognized that the desire to obtain food products from vending machines is heavily dependent upon considerations of time. In dispensing food products at room temperature, or at reduced temperatures, such considerations are not important since the desired food product can be vended directly from the storage compartment of the vending machine. However, in dispensing food products which need to be warmed, or even heated, considerations of time become significantly more important in that a certain amount of time is necessary to properly raise the temperature of the food product which is to be dispensed, prior to its delivery from the vending machine. Indeed, it is generally believed by those in the industry that time periods of even two or three minutes could represent a significant impediment to the interest on the part of the general public in obtaining heated food from a vending machine. Prevailing opinion is that consumer interest is generally limited to time periods on the order of one minute, or less, representing a rather short period of time in which to completely heat and vend a given food product.
Yet another consideration is that of the food product which is to be dispensed from the vending machine. Certain types of foods are well suited to rapid heating techniques, using any of a variety of oven types (e.g., electric heating, infrared heating, convection heating, microwave heating, etc.). Examples of these are available with reference to the patents which are identified above. However, it has been found that some food products are not well suited to heating and dispensing from a vending machine. One example of this is the pizza, which the above-described devices are not well suited to handling.
A key reason for this is that despite the wide popularity of pizza, which is one of the largest, single consumed food types in the United States, food service companies have been unable to produce a frozen pizza which is suited to rapid heating and cooking techniques adaptable to a vending machine. Specifically, a pizza which is well suited to microwave cooking, one of the most rapid cooking techniques available, has not yet been developed. As a result of this, vending machines for handling pizza products have not been forthcoming.
The reasons for this are primarily two-fold. First, even the best so-called "microwaveable" pizzas tend to be less than acceptable in consistency. Available pizza products exhibit drawbacks ranging from very poor taste, to unacceptably doughy crusts, extremely and/or hard chewing crusts, uneven cooking, and at times, a cardboard like consistency. Second, available "microwaveable" pizzas could not, even under the best of circumstances, be cooked in less than approximately three minutes, significantly in excess of the period of time deemed advisable for maintaining consumer interest in obtaining a particular food product from a vending machine.
For this reason, although a variety of vending machines have been developed for dispensing heated and/or cooked food products, none has been developed which is capable of satisfactorily vending a pizza (or other equivalent dough-based food product), despite the significant popularity which the pizza enjoys.